Shuttleless loom grippers

ABSTRACT

Loom on which the insertion of the weft thread into the shed is performed by two rapiers which, starting from two opposite sides, meet in the middle of the shed where the one, called the &#39;&#39;&#39;&#39;feed gripper,&#39;&#39;&#39;&#39; transfers to the other, called the &#39;&#39;&#39;&#39;take-off gripper&#39;&#39;&#39;&#39; B, the weft thread which it has pulled from a fixed supply located on the side of the loom, characterized in that the gripper (A, B) of at least one of the rapiers is a gripper with pivoting arms (9, 55) arranged substantially in the manner of a cloth gripper, the front arms (23, 25) of which, forming a pressure tip which a spring (20, 68) tends to close, are directed toward the front of the rapier, while the rear arms (18, 81), the reciprocal drawing together of which causes the opening of the pressure tip, cooperate with a notch (43, 58) of a mobile drive element (37, 52) capable of interlocking, preferably by means of a spring (47, 56), on the front arms, which have been brought together, to keep the tip of the gripper open.

nited States Patent 1 1 1 3,854,505 Duplessy 1 Dee-17, 1974 SHUTTLELESSLOOM GRIPPERS [76] Inventor: Jean Duplessy, Le Sommet, bis, ABSTRACT rueSimon, Loom on which the insertion of the weft thread into y France theshed is performed by two rapiers which. starting [22] Filed: APE 27 1973from two opposite sides, meet in the middle of the shed where the one,called the feed gripper, transl l PP N05 355,008 fers to the other,called the take-off gripper" B, the

weft thread which it has pulled from a fixed supply [30] ForeignApplication Priority Data cated on the side of the loom, characterizedin that the gripper (A, B) of at least one of the rapiers is a Apr. 27,1972 France 72.15999 g pp with p g arms arranged Substam tially in themanner of a cloth gripper, the front arms (23, 25) of which, forming apressure tip which a [58] Fie'ld 139/122 N spring (20, 68) tends toclose, are directed toward the front of the rapier, while the rear arms(18, 81), the [56] References Cited reciprocal drawing together of whichcauses the opening of the pressure tip, cooperate with a notch (43,UNITED STATES PATENTS 58) of a mobile drive element (37, 52) capable ofin- 3,390,707 7/1968 Scherillo 139/122 terlocking, preferably by meansof a Spring (47, 56). 3,602,266 8/1971 Duplessy 139/122 on the fromarms, which have been brought together Primary E.\'aminerHenry S..laudon Attorney, Agent, or FirmDowell & Dowel] B as 52 E 71 to keep thetip of the gripper open.

8 Claims, 15 Drawing Figures PATENTEUZEEIYIQM 3.854505 SHEET 10? 5 dig-186 K M a SHUTTLELESS LOOM GRIPPERS DESCRIPTION OF THE INVENTION Thepresent invention concerns filling carriers for shuttleless looms withtwo rapiers, that is, those in which the weft thread is caught by itsend at the beginning of a reserve supply held by grippers called thefeed gripper placed at the tip of the first rapier to be conveyed up tothe shed and to be taken in relay by another gripper called the take-offgripper located at the point of the second rapier which draws it throughthe shed up to the other edge of the fabric.

The grippers, object of the present invention, penetrate each other whenthey come together at the shed section and have interacting meanscapable of interlocking at the beginning of the return run of thegrippers to bring about their alignment, to open the feed gripper on theweft thread and close the take-off gripper onto said thread by takingadvantage of the opposing pull of the grippers sensibly aligned, one inthe prolongation of the other, the force necessary for moving thegrippers and to assure the transfer of the weft thread from the one tothe other being precisely determined by the pull that the rapiers exerton each other during their return movement. The feed gripper isdesignated by A and the take-off gripper by B.

The attached drawings, provided as examples, will permit one to betterunderstand the invention, the characteristics it presents, and theadvantages which can be obtained from it:

FIG. 1 is a disassembled and perspective view of a gripper A constructedaccording to the invention.

FIG. 2 is a similar view of a corresponding gripper B, likewiseconstructed according to the invention.

FIG. 3 is a perspective and disassembled view of a part of gripper Ashown in FIG. 1.

FIGS. 4 and 5 are plan views of gripper A in closed and open positionrespectively, the upper face of the protective body being superposed inhorizontal section and removed to permit one to see more clearly thearms of the grippers.

FIGS. 6 and 7 are plan views of gripper B in open and closed positionrespectively.

FIG. 8 is a perspective view of a closing element of gripper A.

FIG. 9 is a plan view of gripper B in closed position with the jaws ofits opening mechanism in the phase preceding their intervention.

FIGS. 10 to 12 show, in views as in FIG. 9, the same gripper B and itsopening nechanism in three successive phases of its intervention.

FIGS. 13 to show, in three successive phases, the copenetration andsubsequent separation in the course of which the transfer of weft threadfrom gripper A to gripper B takes place according to the invention.

In a known loom, the opening of gripper A and closing of gripper B attheir conjunction is produced by the thrust of the rapiers in theirforward motion, whereas on the loom of the invention the same movementof the grippers is controlled by a pull that'the rapiers exert on eachother during their return movement.

THE FEED GRIPPER A This gripper contains a protective shield 1 (FIG. 1)to prevent hooking of the warp thread during penetration into the shed.This element has the form of a tube with a rectangular cross section,the vertical lateral sides of which terminate at the front in points 2and the horizontal sides each likewise have in front a V-shaped groove 3in which the thread engages. Each vertical lateral side has a window 4on the front side and a window 5 toward the base on the rear half topermit the opening and closing of the arms of the grippers as will bedescribed below.

The grippers themselves are composed of two similar symmetrical flatarms 9 which can oscillate on a common pin 10 which will be held byscrew 11 over hole 6 of the lower horizontal side of the protectiveshield. The two arms of the grippers on a lug 12 in their center have aborehole 13 through which passes pin 10. The center of said borehole 13is located exactly in the prolongation of the face of gripping surface14 which provides the gripping action.

The rear portion of arms 9 of the grippers each form a pallet 15, theexterior side 16 of which is rounded in the form of a cam surface which,when the grippers are placed flat in the bottom of the protectiveshield, project over the latter and through slot 5 sufficiently topermit one, when the grippers are closed, to open same by exerting, withthe fingers, pressure on cam surface 16 of each arm 9 in order to bringthem together.

The interior sides 17 of pallets 15 have, on their back part, anupwardly directed spur 18 which acts to keep the grippers open by meansof a spring catch described below. They also have an offset 19 formed inpallet 15 which with the back part of side 17 provide lodging for thearms of a closing spring 20 attached to the lower horizontal face of theprotective shield by means of a screw 22 and nut 22a through hole 7.

The two front arms 23 of the grippers on their exterior side have a flatvertical tab 24, the upper part of which is folded toward the inside ina horizontal fold 25. This fold is perforated in the forward part by ahole 26 (FIG. 3) located above and perpendicular to a hole 27 madetoward the front and on the exterior side in each tip of the grippers.Said two holes 26 and 27 are provided for receiving a vertical pin 28around which moves a flap 29 moved into position in a planeperpendicular to the vertical clamp 24 by a flexible helical torsionspring 30.

The flap 29 is a small plate which has above and below two right-angledlugs 33,34 perforated by holes 35 and 36. In the upper part of the flapthere is a folded spur 32. The lower extremity of the spring 30 isinserted into a hole 31 near the base of tab 24 and is fixed in it. Theupper end of the spring is slipped under the folded spur 32 of flap 29and fixed in it. The pin 28 passes longitudinally through spring 30. Thetwo ends of spring 30 are suitably oriented so that, in rest position,flap 29 is positioned in a plane perpendicular to tab 24. This flap canthen oscillate about pin 28 in one or the other direction against theaction of spring 30 which tends to bring it back into a planeperpendicular to tab 24.

The spring catch 37 (FIG. 1) is U-shaped, the two vertical portions 38and 39 of which are pierced by holes 40 and 41 on the same horizontalaxis. The base 42 of said U is flat and has a notch 43 at its front.

Said base 42 on its lower face extending away from notch 43 has aprojection 44 having conveniently the shape of a rounded section. Thecatch 37 is placed inside and toward the back of the protective shield1; it pivots on pin 47 which passes through holes 40 and 41 made in thevertical portions of the catch and through holes 45 arranged in thevertical wails of shield 1. Thus, the catch is positioned in such a waythat projection 44 lodges in a slot 8 made at the base of shield 1, andextends below same, and in such a way that the base 42 of the catch isslightly above the base of the shield so that the catch can oscillate onits pin 47 without being constrained. A spiral torsion spring 48surrounds pin 47 and urges the catch toward a position in which the bendof projection 44 attempts to strike against the front end of slot 8. Forthis, end 49 of spring 48 is introduced into hole 51 made on onevertical wall of the protective shield and is fixed therein, whereas theother end 50 of spring 48 clasps base 42 of the catch and is fixedtherein.

Catch 37 being thus positioned, the notch 43 made in its base surroundsthe two spurs 18 placed behind the arms of the grippers and keeps thelatter in an open position .(FIG. 4).

When a lug G, (FIG. 8) described below, at the beginning of the cycleacts upon projection 44, the catch 37 pivots on its pin 47, its base 42moves back, notch 43 moves away from the spurs 18 which, released, moveaway from each other by the action of spring and the gripper closes(FIG. 5).

THE TAKE-OFF GRIPPER B It is comprised (FIG. 2) mainly of a support tube52 which is shaped like a tube with a very flat rectangularcross-section; it is elongated at its rear by two arms 57 which make itpossible to attach it to the rapier of the loom by means of holes 108.The fore part of the tube is open and has a notch 58 on its upper face.In base 59, which closes the tube at its back part, at the front of arms57 an opening 60 is made, which is smaller than the internalcross-section of the tube.

The rapier head 53 is a flat piece, the main body of which can beintroduced and slid into support tube 52. In the forward part of therapier head the two points 54 are provided which form a V-shaped opening61 between them where the thread is introduced, and each of the two saidpoints has a hook on the outside of the V. This rapier head 53 isextended at the back by a narrow tongue 63 which can enter and slide inthe opening 60 arranged in the base 59 of the tube 52. Said tongue ispierced at the end by a hole 64 for receiving a pin 65. Two holes 66 and67 are likewise made in the rapier head body on the longitudinal axisthereof at suitable locations.

The arms 55 of gripper B are two hoop irons resembling the arms ofchisels and are symmetrical, but each is located entirely on itsrespective side of a common pm.

Toward the middle of each arm a lobe 72 is pierced by a hole 73 whichallows the two arms to receive a common pin 71. The extension of theinside edge 74, by which the arms 55 come into contact with each otherwhen the gripper is closed, passes through the axis of the common pin71. The rear part of the arms of the gripper forms a pallet 79, theexterior side of which in outline forms a rounded boss 80 large enoughso that it passes laterally beyond the rapier head even when the gripperis open.

At their rear extremeites these arms 55 end in spurs 81 capable, whenthe gripper is open, of fitting together in notch 58 of support tube 52which then keeps the gripper open.

The two arms are mounted on the rapier head 53 by common pin 71 fixed inhole 66. When the gripper is open, these two arms do not extend beyondthe breadth of the rapier head (except for their bosses 80) so that thehooks of the rapier head project over the breadth of the rapier head andthe two arms of the gripper. The closing spring 68 is attached totherapier head by screw 69 inserted into hole 67. This spring is kept abovethe arms 55 of the gripper B without impeding their action by anexpanding ring 84 which is as thick as the two arms of the gripper whensuperposed. The ends of closing spring 68 are slid under tongues 78arranged between two slits on the interior sides of the arms of thegripper so as to urge the latter toward its closed position. The rapierhead thus equipped is introduced into the support tube 52 where the rearend of its main body can slide into contact with base 59 of the tubeagainst which it will rest.

The small tongue 63 of the rapier head crosses opening arranged in thebase 59 of the tube 52 and extends between the two arms 57. A spiralcompression spring 56 is slid over said tongue 63 and is covered bysleeve 82. A washer 83 is slipped onto the end of tongue 63 to compressspring 56 and is kept in this position by a pin inserted into hole 64.It is to be understood that by the action of the return spring 56 whenthe gripper is open (FIG. 6) the two spurs 81, which are consequentlydrawn together, are engaged in notch 58 of the support and that thegripper thus remains in an open position against the action of theclosing spring 68.

On the other hand, if it is drawn over the rapier head 53 against theaction of return spring 56, it will slide into the support tube 52.Under the action of the closing spring 68, the rear parts of the arms ofthe gripper, released from the impediment of notch 58, open up and thegripper closes (FIG. 7). The sleeve 82, which covers the return spring56, is of a suitable length so that the advance of the rapier head intothe support tube 52 is sufficient to release spurs 81 from notch 58 butnot needlessly greater.

DRIVE STOP (G) CLOSING THE FEED GRIPPER A It is located on the side ofthe loom where the rapier of gripper A is, apart from the shed, at aplace convenient so that its action on projection 44 of catch 37 closesgripper A on the end of the weft thread at the exact location that saidthread is presented to the gripper by the usual selection devices.

The stop G has theform of a half-segment 85 (FIG. 8), the arc of thecircle of which is turned upward, the horizontal cord downward, and therise is vertical. Said half-segment 85 is located at the end of a thinelastic plate 86 attached at its other end to a fixed point 87. It is tobe understood that when gripper A advances, the stop G will press backprojection 44 and with it catch 37, which will make the gripper close,whereas, when the gripper returns at the end of the cycle, projection 44of the catch coming against the end of the slot 8 will flex spring 86and the stop will not affect catch 37.

REOPENING MECHANISM OF TAKE-OFF GRIPPER B In order that the weft thread,after having been drawn across the shed, is then to be released bygripper B, a mechanism for reopening the gripper is provided, which canbe located at a convenient point beyond the material on the path of saidgripper so as to reset itin the opening position and to feed the end ofthe weft thread to it exactly at the outlet point of the shed.

This mechanism is comprised mainly of two horizontal segments of circle89 (FIG. 9 to 12) from 45 to 60 forming two kinds of jaws pivoting ontwo vertical pins 90. These two segments 89 are located in regard toeach other at a distance such that when they describe a movement ofpartial symmetric rotation they leave between them a space sufficientlysmall so that the bosses 80 of gripper B come into contact with segments89 and make the gripper open. The linear velocity of the arcs ofsegments 89 in their rotation should be slightly higher than thedisplacement velocity of the rapier in order to fascilitate the engagingof spurs 81 in notch 58 of the support tube, the engaging of which isaided by the action of spring 56. Synchronization of the movement of thetwo segments 89 can be assured by two cogged segments, respectivelyintegral with segments 89, geared one against the other and moved by anyknown means, for example, by the action of a lever, the end of whichshould rest on a cam suitably located on a rotating shaft of the loom.

OPERATION It is acknowledged that the gripper A starts on the rightwhere the thread supply is located and that gripper B starts on theleft.

The grippers begin to advance. Gripper A begins in open position on theright (FIG. 4), it encounters the thread presented by an eyelet at themoment the stop G comes into contact with projection 44 of catch 37which moves back, the gripper closes on the thread (FIG. 5) and pulls itacross the shed. Simultaneously, gripper B starts in open position onthe left.

The jaws 89 are turned aside from the fabric and allow it free passageto gripper B and the rapier. Gripper B, now open, penetrates the shed.Having arrived at the center of the fabric, the two grippers cometogether at a variable depth, gripper A always holds the thread, gripperB is always open.

The rapiers begin to start the grippers back and before theirseparation, gripper B, upon closing, opens gripper A and the thread istransferred.

Details of the mechanism for making this transfer will be given below.The grippers withdraw from the shed; gripper A is open and empty,gripper B is closed and carries the weft thread along to the second halfof the widith of fabric. When gripper A proceeds to the right of theshed, it meets stop G, projection 44 of the catch deflexes the springplate 86, so that the stop is ineffective, and the gripper arrives atits initial open position.

Simultaneously, gripper B, closed, moves to the left of the shed underthe effect of the cam placed on the rotation shaft of the loom havingcarried along the weft thread. Segments 89 of the opening mechanismpivot One will recall from the very first that gripper A arrives in aclosed state with the weft thread clamped between its tips, whilegripper B arrives on its side in an open state. The thread should beintroduced between the tips of gripper B and the latter should closewhile gripper A simultaneously remains open.

FIG. 13 shows the two grippers at the moment they penetrate each other.It can be seen that the rapier head 53 and gripper B are narrow enoughto easily penetrate the protective shield l of gripper A even if they donot appear exactly in the center line of said shield in order to opentoward the right the flaps 29 against their return springs 30 whichoffer but negligible resistance.

The mutual penetration can be continued simply (FIG. 14) until the basesof the V-shaped openings of the two grippers are superposed, whichrepresents substantial travel tolerance. When the grippers begin to moveback, they do not undergo any action until the hooks 62 of the rapierhead of gripper B encounter the flaps 29 which strike and slide againstthe lateral sides of the rapier head. At this moment (FIG. 15) hooks 62cause the flaps 29 to move back to the left to allow passage. Uponmoving back, said flaps, while being supported on their pins 28, spreadapart the tips of gripper A which opens, the spurs l8 engaging notch 43of the catch; gripper A remains open, the thread is released. Butsimultaneously, hooks 62 encounter, from flaps 29, a slight resistanceby traction, sufficient never-the-less to slide the rapier head 53 intoits support 52 against the action of return spring 56. Spurs 81 of thearms of gripper B are disengaged from notch 58 of the support; gripper Bcloses again by the action of spring 68 and grips the weft thread at thesame time that it is released by gripper A.

Thus, the invention makes it possible to establish a system of grippersfor shuttleless looms with two needles or rapiers, the tension of whichis by positive action, therefore capable of gripping and pulling threadsof completely different sizes and types without preliminary adjustment,and the good operation of which does not require dimensional precisioneither in coming together or in mutual penetration.

I claim:

1. In a loom on which the insertion of weft threads into successivesheds is accomplished by two gripper rapiers, a feed gripper A and atake-off gripper B which, starting from opposite sides, meet in themiddle of a shed where the feed gripper A transmits to the take-offgripper B, a weft thread which it has drawn from a fixed supply locatedon one side of theloom, and characterized in that the grippers penetrateeach other when they meet in the middle of the shed; each gripper beingprovided with a cooperating means (29 62) which while said grippers arein the prolongation of each other act to mutually interlock at thebeginning of the return run of said grippers so as to ensure thealignment thereof; to open gripper A to release the weft thread, and toclose gripper B on to the same weft thread, said actions being broughtabout by the opposite pull of said grippers.

2. A loom as in claim 1, wherein gripper A includes a pair of pivotedarms (9) having front portions (23), pins (28) each mounted on one ofthe portions (23) pivotally mount flaps 29 perpendicular to theclearance plane of the arms springs (30) carried by pins (29) act tomaintain said flaps in position to provide a pivotal gate (23) on thelateral faces of the gripper A said gate being in the path of take-offof gripper B and capable of allowing free forward passage and freeoutward passage to at least the part before the tip of the gripper B,said tip comprising means (54, 62) capable of moving apart said flaps(29) on'their forward run and of engaging said flaps on the return runso as to act against pins (28) and thereby force open the tip of gripperA against the pressure of closing spring (20); the resistance of saidencounter exerting a force on gripper B which brings about the closingof its gripper member.

3. A loom as in claim 1, characterized in that the gripper A isprovided, adjacent to the inward ends of arm (9), with a pin (47)mounted perpendicular to the axis of pin (10), catch (37), which hasnotch (43) formed therein, is pivotally mounted on pin (47) and urgedinto an operative position by spring (48), said catch (37) extendsoutward of the contour of the gripper, a stop (G) is positioned alongthe path of the gripper in position to engage said catch at thebeginning of the forward run of said gripper which engagement causesnotch (43) to release spurs (l8) and allows the gripper to close on theweft thread.

4. In a loom on which the insertion of weft threads into successivesheds is performed by two rapiers, a feed rapier having a gripper A anda take-off rapier having a gripper B, which starting from opposite loomsides meet in the middle of a shed where the feed gripper A transfers tothe take-off gripper B, a weft thread which it has pulled from a fixedsupply located on one side of the loom; and characterized in that thegripper (A, B) of at least one of the rapiers comprises pivoting arms(9,55), said arms comprising front portions (23,25) located adjacent forforward portion of said rapiers, spring (20,68) mounted about thepivotal axis of said arms act to urge said front portions together, rearportions (18,81) of said arms (9,55) cooperate with notch (43,48) formedintegral with a mobile drive element (37,52) carried by said gripperA,B, said element (37,52) functioning to release the gripper arms tosaid gripping position or to keep the front portions of said armsseparated.

S. A loom as in claim 2, characterized in that the means (62) of gripperB comprises at least a pair of harpoon-like hooks which extend beyondthe opposite lateral sides of said gripper when open.

6. A loom as in claim 5, characterized in that gripper B carries a plate53 which has one end formed as parallel extensions the ends of whichcomprise hooks (62), plate (53) is provided with a pin ,(71) whichpivotally mounts a gripping element and a closing spring (68), spring(68) acts against tongues (78) of said gripping element to urge arms(55) into mutual contact; said extensions are shaped in the form of a Vhaving an angle which coincides approximately with that of arms (55)when in the open position.

7. A loom as in claim 6, characterized in that gripper B includes asupport tube (52) in which plate (53) is slidably mounted, said tube(52) is formed with a notch (58) which acts to receive and retainopposite ends (81) of gripper arms (55) so as to retain same in the openposition, spring (56), integral with tube (52), is engaged with plate(53) so as to urge same inwardly of said tube to a position in whichends (81) of arms 55) are received in notch (58) and retained in an openposition, plate (53) is urged toward the outside of tube (52) duringinitial outward movement of grippers A,B which movement releases ends(81).

8. A loom as in claim 7, characterized in that the arms 55 have formedat their opposite ends control bosses (80) which protrude from oppositesides of the gripper B, a pair of jaws 89 are mounted adjacent to theextreme withdrawn position of said grippers and in the path of bosses(80) so that when said grippers move to said withdrawn position saidjaws act on said bosses to urge against spring 68 and move end portions(81) into position to be engaged by notch (58).

1. In a loom on which the insertion of weft threads into successivesheds is accomplished by two gripper rapiers, a feed gripper A and atake-off gripper B which, starting from opposite sides, meet in themiddle of a shed where the feed gripper A transmits to the take-offgripper B, a weft thread which it has drawn from a fixed supply locatedon one side of the loom, and characterized in that the gripperspenetrate each other when they meet in the middle of the shed; eachgripper being provided with a cooperating means (29, 62) which whilesaid grippers are in the prolongation of each other act to mutuallyinterlock at the beginning of the return run of said grippers so as toensure the alignment thereof; to open gripper A to release the weftthread, and to close gripper B on to the same weft thread, said actionsbeing brought about by the opposite pull of said grippers.
 2. A loom asin claim 1, wherein gripper A includes a pair of pivoted arms (9) havingfront portions (23), pins (28) each mounted on one of the portions (23)pivotally mount flaps 29 perpendicular to the clearance plane of thearms springs (30) carried by pins (29) act to maintain said flaps inposition to provide a pivotal gate (23) on the lateral faces of thegripper A said gate being in the path of take-off of gripper B andcapable of allowing free forward passage and free outward passage to atleast the part before the tip of the gripper B, said tip comprisingmeans (54, 62) capable of moving apart said flaps (29) on their forwardrun and of engaging said flaps on the return run so as to act againstpins (28) and thereby force open the tip of gripper A against thepressure of closing spring (20); the resistance of said encounterexerting a force on gripper B which brings about the closing of itsgripper member.
 3. A loom as in claim 1, characterized in that thegripper A is provided, adjacent to the inward ends of arm (9), with apin (47) mounted perpendicular to the axis of pin (10), catch (37),which has notch (43) formed therein, is pivotally mounted on pin (47)and urged into an operative position by spring (48), said catch (37)extends outward of the contour of the gripper, a stop (G) is positionedalong the path of the gripper in position to engage said catch at thebeginning of the forward run of said gripper which engagement causesnotch (43) to release spurs (18) and allows the gripper to close on theweft thread.
 4. In a loom on which the insertion of weft threads intosuccessive sheds is performed by two rapiers, a feed rapier having agripper A and a take-off rapier having a gripper B, which starting fromopposite loom sides meet in the middle of a shed where the feed gripperA transfers to the take-off gripper B, a weft thread which it has pulledfrom a fixed supply located on one side of the loom; and characterizedin that the gripper (A, B) of at least one of the rapiers comprisespivoting arms (9, 55), said arms comprising front portions (23,25)located adjacent for forward portion of said rapiers, spring (20,68)mounted about the pivotal axis of said arms act to urge said frontportions together, rear portions (18,81) of said arms (9,55) cooperatewith notch (43,48) formed integral with a mobile drive element (37,52)carried by said gripper A,B, said element (37,52) functioning to releasethe gripper arms to said gripping position or to keep the front portionsof said arms separated.
 5. A loom as in claim 2, characterized in thatthe means (62) of gripper B comprises at least a pair of harpoon-likehooks which extend beyond the opposite lateral sides of said gripperwhen open.
 6. A loom as in claim 5, characterized in that gripper Bcarries a plate 53 which has one end formed As parallel extensions theends of which comprise hooks (62), plate (53) is provided with a pin(71) which pivotally mounts a gripping element and a closing spring(68), spring (68) acts against tongues (78) of said gripping element tourge arms (55) into mutual contact; said extensions are shaped in theform of a V having an angle which coincides approximately with that ofarms (55) when in the open position.
 7. A loom as in claim 6,characterized in that gripper B includes a support tube (52) in whichplate (53) is slidably mounted, said tube (52) is formed with a notch(58) which acts to receive and retain opposite ends (81) of gripper arms(55) so as to retain same in the open position, spring (56), integralwith tube (52), is engaged with plate (53) so as to urge same inwardlyof said tube to a position in which ends (81) of arms (55) are receivedin notch (58) and retained in an open position, plate (53) is urgedtoward the outside of tube (52) during initial outward movement ofgrippers A,B which movement releases ends (81).
 8. A loom as in claim 7,characterized in that the arms 55 have formed at their opposite endscontrol bosses (80) which protrude from opposite sides of the gripper B,a pair of jaws 89 are mounted adjacent to the extreme withdrawn positionof said grippers and in the path of bosses (80) so that when saidgrippers move to said withdrawn position said jaws act on said bosses tourge against spring 68 and move end portions (81) into position to beengaged by notch (58).